Mirror Mirror
by cassikat
Summary: What if the hand in the jar didn't turn into a duplicate of the Doctor, but instead turned into a duplicate of Donna?  It'll be cracktastic!


Disclaimer: Er, yeah, there's no way this could ever happen in canon. That's why this is fanfiction of the crack variety.

Warnings: Crack. Well, mostly. And naughty language.

AN: It's all tkelparis' fault, since she's the one who started the alternate Handy challenge on doctor_donna :D She also betaed, for which, as always, much thanks! *mwah!*

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><p>Mirror, Mirror<p>

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><p>As the TARDIS suffered and burned around her, the heartbeat was suddenly all she could hear again, this time, pounding in time to her own heart. It seemed to direct her attention to the hand in the jar, and, ignoring the chaos around her, she reached out to touch it...and it seemed like the world exploded in golden-orange energy that engulfed her, flowed through her, then flowed back into the hand to shatter the jar and leave it on the grating.<p>

A bit dazed from what had just happened, Donna watched the glowing hand - as it's fingers became more feminine just before the glow spread out into a human shape. When it faded, Donna blinked at...herself, lying naked on the floor.

"Wot?" her twin asked as she sat up and noticed Donna staring at her, then blinked and said, "Oh that's weird. New voice?"

"Oh. My. God!" Donna exclaimed. "You...you're me!" she added with a squeak at the end.

"Am I?" the duplicate asked, then looked down at herself. "Oh. My. God! I'm you! You're me!" Another explosion of sparks came from the TARDIS console, startling both of them and the naked Donna jumped up and pressed a button. "Blimey! All right, all right," she said as she fiddled with the TARDIS console until the old girl was out of the core of the Crucible and the smoke was clearing.

"Right," Donna said firmly, staring at her twin who was taking advantage of a temporary lull in the crisis to examine her breasts. "Enough of that! You should know how many freckles we've got on our tits, since you're me and all. Just tell me how come you're me? From the Doctor's spare hand? Y'know, I'd think that would mean you'd be a copy of him, not me."

"We really _do_ have a magnificent pair, you know. He thinks that a lot," her twin started, then stopped and looked sheepish. "Sorry, sorry. Well, short explanation is, you're awesome. Longer explanation is...well, you do remember hearing the heartbeat, right?"

"Wot? The Doctor's been thinking about my tits?" Donna yelped, then waved her hand. "Never mind, I'll slap him for it later. And of course I remember hearing the heartbeat, but I've been hearing that a lot over the last day." Donna eyed her twin, then rolled her eyes. "C'mon, let's get you dressed and you can explain on the way."

"It is a bit chilly in here according to my boobs, but the Old Girl's been through a lot." The mirror image stopped looking at her erect nipples, nodded and started down the hall for Donna's bedroom, explanation trailing behind. "You were hearing the heartbeat because I was echoing backward at you, cos believe it or not you're special and magnificent and everything else he keeps telling you and you never believe. And it is so _weird_ - and a bit disgusting - having just one heart-"

"Oi! Less complaining and more explaining, thanks!" Donna glowered at her twin's back and the multitude of freckles on it, then muttered. "And I'm nothing special, just a temp."

"Right, sorry. Well I think it's because right at the end, the heartbeat you were hearing was in exact synchronisation with your own. So I'm your twin instead of his. Brilliant, innit?" She smirked at Donna and walked in the bedroom, then immediately dove for the wardrobe, voice a bit muffled by all the clothes. "And oh please. Do you really think the Old Girl would let you pilot her all by yourself with himself just standing there watching? She loves you, which automatically makes you special so stop with letting Sylvia get you down already!"

"Oh just wizard." Donna snorted and shook her head while she pulled underthings out for her weird twin and tried not to get dragged into an ego-boosting session (even if finding out the Old Girl loved her made her all warm inside). "Yeah, speaking of Mum - can you imagine how I'm going to explain _you_ to her? 'Oh hi mum, you've got twin daughters now because the Doctor's a bloomin' weird alien.' Yeah, that'll go over like a lead balloon."

"Oh bloody hell, Sylvia's my mum," her twin moaned and collapsed on the bed, face buried in the pinstripe suit Donna had worn when she'd found the Doctor again. Then a thought occurred to her and she perked up. "Although technically she's my Nan, since I'm half you and half him. But on the bright side I won't get slapped! Well, probably. Maybe. Possibly?"

"Oh get dressed, we can figure it all out later if we live long enough." Donna hoped they could manage to survive, and save the universe from Daleks...because that might be trickier than anything else she and the Doctor had ever done.

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><p>After both Donnas had panicked appropriately about the reality bomb, Donna was pacing the console room while her twin slumped on the jumpseat trying to think.<p>

"Okay, so I get that it's the end of everything if we don't stop it. So...you'll figure something out, you've got his mind. What you need is a distraction while that part decides what to do..." Donna trailed off, still watching her disconsolate twin. "Distraction, distraction...hah, got it. You said he's been thinking about my breasts. What else has he been thinking about me?"

"Oh I don't believe you! It's the end of everything and you want to know that he got a stiffy when he was cleaning all that depression-inducing slime off you?" Donna II got up from the jumpseat and started gathering bits and bobs.

"No! He did not!" Donna staggered to the jumpseat, staring wide-eyed at her twin. "But...that was just because there was a naked body right there, yeah?"

"Nah. Remember, he thinks our breasts are magnificent." Donna II blanched a bit remembering what else the Doctor thought, then swallowed hard and added a few more bits to what was becoming disturbingly gun-shaped. "He also saw you when you were skinny-dipping in the pool...when you got out, he compared you favourably to Aphrodite. Oh. My. God. Get the memories of him wanking to that image out of my head!"

"Oh. My. God!" Donna gasped. "That...that outer-space...Martian...pervert! I thought he only wanted a mate - a friend!"

"He did. Does. He's just been keeping his physical attraction to himself cos he didn't want you to leave." Donna II sighed and shook her head, still adding things to the gun. "And of course he's still hung up on that whinging blonde emotionally, so it's a confused and guilty secret on top of it all. Really, you'd have just freaked out and told him to keep his wanking to himself. And slapped him, but that would've been the end of it." Donna II scowled and screwed one last piece on, and shook her head. "I could natter on and on about that outer space dumbo and what he really needs but won't or can't realise, but now that I've finished this Zed-Neutrino biological inversion catalyser, we really need to go shoot Davros with it and save the universe."

"Right, we'll gossip about himself later. And remember, just an Earth-girl here - wot's a Zed-Neutrino biowhatsit when it's at home?" Donna stood up and straightened her clothes.

"Davros grew those Daleks out of himself, so his genetic code runs through every single one of'em. So, if I can use this to lock the Crucible's transmission onto Davros..."

"Oh. Then instead of the universe, the Reality Bomb will destroy the Daleks." Donna frowned in concern. "Suppose we're too short on options to do it any other way, yeah?"

"Yeah. It's the Daleks or the universe...and frankly I pick the universe." Donna II had a bleak look as they stared at each other, remembering the last time a choice like this had to be made.

Donna's expression matched her twin's for bleakness as the weight of what they were about to do sank in, then they nodded in unison. "Right, let's get us back there and get it done with."

"Oh yes! We'll show them what we're made of all right." Donna II grinned, then handed the gun to her twin. "Hold this a moment," She kicked a lever, pulled another one, and the TARDIS slewed sideways before materialising. "Stay safe, twin." She smiled and took the device and opened the door, pausing a moment before charging out at Davros.

Pity she only made it half-way there before he zapped her and trapped her in a holding cell.

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><p>The Doctor stared in disbelief as the TARDIS materialised and Donna stepped out...but why did she change clothes? He shouted a warning as she ran toward Davros, but it was too late - he'd zapped her and she'd lost - was that a gun? Oh, no - it was a zed-neutrino biological inversion catalyzer. But how did Donna - who couldn't change a plug - build that?<p>

His question was sort of answered when Donna again bolted from the TARDIS and scooped up the catalyzer, only to panic and yell at her twin asking what to do. Before she could answer herself though, Davros blasted her backwards and smirked, then ordered the catalyzer be destroyed.

"...human biological metacrisis," he murmured in disbelief and shook his head. "But why two of Donna?"

"Oi! There's nothing wrong with two of me, Time Boy!" snapped the Donna in the holding cell. "And you, Davros! Did anyone ever tell you that you were really, _really_ stupid? I mean, come on! Yeah, you're going to destroy the universe so there'll be nothing left but Daleks. But history proved that even Daleks will split into factions - your precious children are going to destroy themselves when there's nothing else left to kill! What're you going to do then?"

"My Daleks will never destroy themselves. Now watch," Davros activated a holographic screen showing all the kidnapped planets. "Your strategies have failed, your weapons are useless...and oh, the end of the universe is come."

"Meh. Maybe. And maybe not," Donna II said, over the countdown, distracting everyone from Donna meddling with a bank of controls.

Well, until the screen shut itself off and the rising whine of the Reality Bomb died abruptly. Donna II smirked, put her hands on her hips and said. "Never underestimate Donna Noble."

From the bank of controls, Donna smirked too and said. "Oh... closing all Zed-Neutrino relay loops using an internalised synchronous back-feed reversal loop! That button there!"

"But Donna, you can't even change a plug!" The Doctor sputtered, baffled at the idea of two of Donna, acting just like him.

"Oh piffle," snorted the Donna in the holding cell. "Shut up and let Donna do her thing." Which happened at that moment to be briefly electrocuting Davros and explaining how she did it. And then likewise with shutting down the Daleks' weapons.

"But...but...biological metacrisis isn't supposed to-" The Doctor babbled, trying to figure out what happened.

"Is if it's two-way," smirked the Donna in the holding cell. "Which really only makes sense you know. I'm Donna with your mind...and so is she. Both of us part human, part Time Lord."

"Except I didn't grow from your hand, Doctor," the Donna by the controls grinned. "I just got your mind - the best part of you. But we are really gonna have to talk later about some of the things you have ratcheting around up there, you prawn."

"Blimey!" The Doctor exclaimed, while blushing furiously and firmly deciding -not- to ask what she thought of some of the things he'd been thinking about her. (He also decided to completely ignore Jack and his speculative looks and comments...but, well, he mostly did that anyway) "The Ood, remember? The Doctor-Donna - they saw this coming all along! Well, except for there being two of you, but still!"

Rose had a confused frown and wondered why he blushed. But she figured that Donna had memories of his feelings for her, and he was embarrassed that he might get teased about it.

Meanwhile, Donna had deactivated the holding cells and made the Daleks spin uncontrollably to keep them occupied. "Don't just stand there like nimrods twin, Doctor, get to work!"

"Do you have to show off, twin?" Donna II groused as she picked a spot to work at.

"Course I do. You and the Doctor, you're hampered by being just Time Lords. Or mostly Time Lord. Me, I got his mind and that brilliant human spark - I can think of ideas you two couldn't in a million years. Well, maybe you will, when you learn to listen to your human bits." She raised her voice when she heard Jack snickering. "And I don't mean _those_ bits, you intergalactic lech!"

"Brilliant. Just...brilliant!" The Doctor grinned as Donna sent the trip-stitch all over the ship.

"You better believe it, Spaceman." Donna grinned along with her twin, then gestured. "Now lets send those planets back where they belong!" And they did. Except for one of course.

And there was an angry bit of shouting when the Donnas destroyed the Daleks while the Doctor was busy configuring the TARDIS to tow the Earth home. But since they were right when they said it was the Daleks or the Universe, they figured they'd slap some sense into the Doctor later.

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><p>Later, when the argument over the fate of the Daleks went way south - with all three of them saying nearly unforgivable things - and the Doctor dumped the two Donnas back in Chiswick for genocide (the hypocrite!), Donna had sat down to explain how she was suddenly twins to Mum and Gramps. It was noisy, and included a recap of nearly everything that had happened, but in the end Sylvia had finally surrendered to the fact that she technically had a granddaughter, although she insisted she be called Aunt Sylvia, if they were going to pass the twin off as an identical cousin. Wilf, of course, was tickled pink to have what might as well be a female version of the Doctor as part of the family, and insisted she call him Gramps too...and he was the one who suggested the duplicate Donna use Donna's middle name, Marie.<p>

Dinner was eaten, unpacking (and settling Marie into the spare room) was done, and finally the twins were left alone on a sofa, huddled together and watching the rain pour down.

"Be about a week of it pissing like this, cos of the atmospheric disturbance," Marie muttered absently, still aching from being evicted from the TARDIS, and missing the Old Girl horribly. "I wish he hadn't been so...no second chances about us."

"Yeah, I know." Donna hugged Marie briefly, still incredibly angry with the Doctor. "Stupid git. At least he gave us time to pack. Which gave the TARDIS a chance to slip us this." She pulled a good-sized piece of TARDIS coral out of her pocket and managed a grin. "I figure we can shatterfry the plasmic shell and modify the dimensional stabiliser to a foldback harmonic of 36.3, which will accelerate the growth by the power of 59. Which still means a year, probably, but we'll be out in the universe before we're old and grey."

That got Marie's attention, and she stared at the coral for a long minute before smirking. "Well, given that I nicked this," she pulled the Doctor's sonic screwdriver out of her pocket, "Yeah, I think we can do just that. And if we can talk Jack into letting us draw from the Rift, we can double that growth rate with a stabilized feedback power loop resonating at 25.9 on top of it!"

The twins grinned smugly at each other, and said in unison. "The universe won't know what hit it."


End file.
